In producing petroleum and other useful fluids from production wells, it is generally known to provide a submergible pumping system for raising the fluids collected in a well. Production fluids enter a wellbore via perforations formed in a well casing adjacent a production formation. Fluids contained in the formation collect in the wellbore and may be raised by the submergible pumping system to another zone or to a collection point above the surface of the earth. Submergible pumping systems also are used to inject fluids into the formation to contain or move a reservoir of production fluid so that it may be produced more readily from a given location.
In an exemplary electric submergible pumping system, the system includes several components, such as a submergible pump, a submergible electric motor and motor protector. The submergible electric motor typically supplies power to the submergible pump by a drive shaft, and the motor protector serves to isolate the internal motor oil from the well fluids. A deployment system, such as deployment tubing in the form of coiled tubing or production tubing, is used to deploy the submergible pumping system within a wellbore. Generally, power is supplied to the submergible electric motor or motors by one or more power cables supported along the deployment system.
Some wells have the capability of producing from two or more zones or reservoirs. However, because of constraints, such as incompatibility of fluids, differential pressures in the reservoirs, and other constraints, it sometimes is undesirable to commingle the fluids produced from separate production zones.
Production from the separate zones or reservoirs can be accomplished by running separate electric submergible pumping systems along side of one another and deployed on separate tubing strings. In some applications, however, this may be problematic due to space constraints. In other words, the wellbore must be of substantial diameter to accommodate two separate systems that are deployed along side of one another. These problems are equally applicable if one of the systems is used for injection of fluids, while the other is used for production of fluids.
It would be advantageous to have a dual electric submergible pumping system that could be deployed either on a single tubing deployment system within a narrowly confined wellbore, or on a pair of tubing deployment systems with the two or more electric submergible pumping systems arranged generally axially. Additionally, it would be advantageous to utilize separate fluid flow paths to prevent commingling of fluids pumped from or injected into separate zones.